Automatic starter for internal combustion engines



Dec. 10, 1968 R. P. NOURY AUTOMATIC STARTER FOR INTERNAL COMBUSTIONENGINES F iled Dec.

3 Sheets-Sheet l Dec. 10, 1968 R. P. NOURY AUTOMATIC STARTER FORINTERNAL COMBUSTION ENGINES 3 Sheets-Sheet 2 Filed Dec.

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AUTOMATIC STARTER FOR INTERNAL COMBUSTION ENGINES Filed Dec. '1, 1965 v3 Sheets-Sheet 5 7% 0/2 PRISSl/flf SWITCH AC. or 0.6 GENERATOR m/v/r/b/vcoil United States Patent 3,415,999 AUTOMATIC STARTER FOR INTERNALCOMBUSTION ENGINES Roger P. Noury, 8927 Tolhurst St., Montreal, Quebec,Canada Filed Dec. 1, 1965, Ser. No. 510,849 25 Claims. (Cl. 29038)ABSTRACT OF THE DISCLOSURE An automatic starter for motors having anignition coil energized by a DC-power supply and operated by a lowfrequency bi-stable trigger circuit comprising two time delay switcheswhich via a power transistor and for a given period of time conductcurrent to a starter motor after which period and upon failure to startthe motor, a third time delay switch deenergizes the first two timedelay switches and arranged so that in case the motor is started aswitch responsive to the motor is actuated and deenergizes the ignitioncoil and the third delay switch.

The present invention relates to an automatic starter for motors andparticularly for internal combustion engines.

The automatic starter may be placed in operating condition by closing asimple switch or actuating a remote control device. The automaticstarter may also be actuated by a temperature control switch at acertain temperature.

The automatic starter is adapted to turn the starter motor for shortperiods only until the motor runs. A start and stop process for thestarter motor is preferred in order to save the battery. This processalso forms a more positive way of starting the motor than to let thestarter motor run until the battery is discharged.

Upon energizing the starter motor once or for a few times, the enginewill normally run. A motor responsive switch will then stop theoperation of the automatic starter.

The motor will run until it is manually stopped, that is, if it has beenstarted by a sole switch or by a remote control device only. In case themotor has been started through an auxiliary, temperature-controlledswitch, said switch will stop the motor when same has reached apredetermined high temperature. The cycle of operation is institutedbetween predetermined upper and lower temperatures. This operation cyclehas the advantage of maintaining the motor above a certain temperaturein order to facilitate its starting operation.

If the motor has not started to run after a predetermined number ofstarting attempts, a communicating circuit is actuated and stops theoperation of the automatic starter.

An advantage of this device is to warm up the engine by turning on aswitch which may be located inside a house or at least away from theengine. If the thermostat located in the neighborhood of the engineindicates that the latter is cold, the engine will start to run until itreaches a determined temperature.

This operation may take place in the morning, for instance some timebefore the operator expects to use his car.

When particularly cold weather is expected, a manual switch may beactuated the night before and the automatic starter will actuate themotor at various intervals during the night in order to maintain themotor in an easy-tostart condition.

When the motor starts to run, a motor responsive switch stops theactuation of the automatic starter. The motor responsive switch may be aconnection located at the Patented Dec. 10, 1968 generator forindicating the actuation of the generator or an oil pressure switch.

In order to obtain the above-indicated results, it has been conceived touse low frequency oscillators in time delay switches. One of said delayswitches is alternately actuated in order to energize a starter motor. Athird delay switch containing a third oscillator having a longer periodthan the first two ones comes into operation after a number of cycles ofthe time delay switches have failed to start the motor.

The first two time delay switches operating alternatively may beconsidered as a bi-stable trigger circuit or a multivibrator.

The three oscillators may be a silicone unijunction transistor connectedin series with a number of resistors and a capacitor. The siliconeunijunction transistor provides a low frequency oscillation. Theunijunction transistor is connected in parallel with a siliconecontrolled rectifier, one terminal of the unijunction transistor beingconnected to the gate of the said controlled rectifier. The combinationof the said oscillator with the controlled rectifier constitutes a timedelay switch. Two such time delay switches having diiierent operationperiods may be connected to alternately actuate a relay in order toenergize in a discontinuous manner a starter motor. The combination ofthe said two time delay switches constitutes a low frequency bi-stabletrigger circuit.

A substantially similar oscillator such as the two previously mentionedones but having a longer period of oscillation may be connected to athird controlled rectifier and a third relay to constitute a third timedelay switch which will stop the actuation of the trigger circuit aftera determined number of cycles will have taken place.

A different embodiment of the invention is formed by introducing in thearrangement of the automatic starter, a combination of power transistorswhich will eliminate the use of relays. In this case, power transistorwill alternately be actuated by a controlled rectifier and blocked, atregular intervals, by a time delay switch.

The time delay switch which eventually stops the operation of thetrigger circuit may essentially consist of the combination of a powertransistor, a unijunction transistor and a controlled rectifier withappropriate resistors and capacitors.

It is obvious that various embodiments may include a choice ofcombinations of time delay switches comprising relays or powertransistors.

It is also understood that a timing device may be incorporated in thecircuit to start the operation of the automatic starter at a given time.

Various other modifications will become apparent to those skilled in theart from the following description taken in conjunction with theaccompanying drawings, in which:

FIG. 1 shows an automatic starter comprising a bistable trigger circuitwhich includes one relay.

FIG. 2 represents the circuit for an automatic starter comprising abi-stable trigger circuit which includes a relay for each of the timedelay switches.

FIG. 3 represents a circuit for an automatic starter without the use ofany relays.

FIG. 4 represents a circuit for an automatic starter comprising abi-stable trigger circuit without relays, however, in which a relay isused in the time delay switch for stopping the bi-stable triggercircuit.

Before explaining the operations of the circuits shown in the figures,it may be useful to provide some general information about the elementsshown in the drawings.

In FIG. 1, there are four relays A, B, C and D. Three of these relaysare shown as being connected in parallel with a rectifier diode so thatthe diode prevents a feedback into the relays. The contacts which formspart of each relay have been shown throughout the circuits by the sameletter as the one used for the corresponding relay with an index 1, 2 or3. Furthermore, if the contact is normally opened, it has been indicatedas NO. and if normally closed, the letters N.C. have been added. Forinstance, the relay A has two normally opened contacts A and A The relayB has two normally opened contacts B and B and a normally closed contactB Similarly, normally closed contact C is operated when relay C isenergized and normally closed contact D operates when the relay D isitself energized. The transistors identified by U in the disclosure areof the silicone unijunction type which have a very high time constant.The transistors generally identified in the disclosure by SC are of thesilicone controlled rectifier type which will permit the current to passwhen a current is fed to its gate by a silicone unijunction transistor.

Now referring to FIG. 1, the toggle switch T.S. is closed to prepare theautomatic starter to operate automatically. As it may be seen in thefigure, switch SW1 is simultaneously closed.

When the temperature falls below a given degree, the thermostat THswitch closes. The relay A is then ener gized and institutes closing ofcontacts A and A When A closes, the ignition coil is energized. When A,closes, the operation of the time delays which may be generallyidentified by U U and U starts. The combination of U R R R and capacitor14 forms a low frequency oscillator having the shortest time constant inthe circuit. After a short period, this combination will energize therectifier SC The current will then pass through the relay B for a givenperiod. When the relay B is energized, its normally opened contacts Band B close, and the normally closed contact B opens. B in the closedposition operates the starter motor.

The motor may start immediately, and if it does, a current will be drawnfrom the generator (A.C. or DC.) and energize the relay D. Normallyclosed contact D which belongs to the relay D, deenergizes U U U and thestarter.

The motor runs until it reaches an upper determined temperature at whichthe time switch TH is opened.

At this time, the motor stops, the relay D is deenergized and itscontact D closes. The relay D may also be referred to as a crankingcut-out relay because it is the relay that cuts out the automaticstarter when the motor starts to run.

It the motor does not start to run on the first try, the relay B stopsto be energized at the end of the period of the oscillator U at whichtime B, and B open and B closes. The starter also stops being energized.

After a given period which is longer than the period of U and measuredaccordingly, U becomes energized and the rectifier SC becomesconductive. The relay B will again be energized and accordingly,contacts B and B will close, contact B will open and the starter motorwill be energized.

It should be pointed out here that the transistor U with the resistors RR R and the capacitor form an oscillator with a longer time constantthan the combination comprising the transistor U These two oscillatorsin combination with their respective controlled rectifiers 5C and 8Calternately act on the relay B and constitute two time delay switcheswhich function as a trigger circuit or multivibrator. This circuit willbe actuated for a determined number of cycles.

If during one of the cycles, the motor starts, the procedure statedabove will take place. If the motor has not started before the end ofthe given number of cycles, a third time delay switch is arranged tostop the operation of the flip-flop circuit. The third time delay switchcomprises the unijunction transistor in combination with the resistors RRa,,R and capacitor 16 with the controlled rectifier SC and the relay C.The third time delay switch operates in a similar manner as each of thefirst two delay switches mentioned hereinbefore. The third time delayswitch has a period equivalent to a given number of said cycles. Whenthe third delay switch generally identified by U has reached its delayperiod, the rectifier SC becomes conductive and enables the current topass through the relay C. When the relay C is energized, its contact Copens. The relay A will then become deenergized and its contacts A and Awill open.

At this time, only the relay C will remain energized until the toggleswitch T.S. is manually opened which will completely stop the operationof the device.

The toggle switch T.S. is usually not opened immediately, but the amountof current passing through the relay C is very small and will not drainout the battery.

FIG. 2 shows a different embodiment from the one represented in FIG 1.Nevertheless, both embodiments operate on the same principles, that is,on the alternative operation of two time delay switches constituting alow frequency trigger circuit.

The switch SW is the switch which enables the operator to put the devicein the automatic position (AUTO) by introducing the thermostat (TH) inthe circuit or to test the device manually (MAN) without having to waitfor the thermostat to operate.

When the switch SW is in the AUTO position, and the temperature fallsbelow a determined degree, the switch TH closes and the following stepstake place:

(a) Relay E is energized and contacts E E and E close.

(b) When E is closed, the time delay U starts to operate.

(c) When E (d) When E (e) The time to operate.

At this time, the motor may start to operate in the same way asexplained with respect to FIG. 1, but if it does not start the processcontinues as follows:

The delay generally represented by U, has the shortest time constant andat the end of its period, the rectifier 8C becomes conductive and thecurrent will then pass through it, to energize the relay F.

The switch F will move from its normal position (full lines to thedotted lines) so that the starter motor will stop being energized andthe delay generally represented by U will start to be fed.

The switch F will move from its normal position (full lines to dottedlines) shown in FIG. 2.

At the end of the period of U the rectifier SC becomes conductive. Thecurrent then passes through the relay G and the normally closed contactG opens which deenergizes the relay F. At that time, the switches F andF operated by the relay F return to their normal position (full lines).

The cycle process of actuating U and U proceeds until the motor startsto run. If the motor has not started by the end of the period of thetime delay, generally represented by U (which takes place at the end ofa determined number of cycles U U the, rectifier 8C becomes conductiveand the relay H becomes energized. At that time, the normally closedcontact H opens and the normally opened contact H closes. The switch Hmoves from its normal position (shown in FIG. 2) to a contact on theright-hand side. The rectifier SC stops being fed. But a current willkeep running through the relay H. The relay H dissipates a very smallamount of current which will not affect the battery to a large extent.

It may be seen from FIG. 2 that the normally closed contact H and thenormally opened contact H may be combined into a single pull doublethrow switch.

The switch SW is operated simultaneously with the switch SW When theswitch SW is in contact position, the cranking cut-out relay 1 will beenergized through the generator when the motor will start. Thisoperation is similar to the one explained in FIG. 1.

is closed, the starter is energized. is closed, the ignition coil isenergized. delay generally represented by U starts FIG. 3 shows anembodiment of an automatic starter with the use of two power transistorsQ and Q without relays as in FIGS. 1 and 2. The current from transistorQ reaches the transistor Q goes through the emitter of Q and down thecontrolled rectifier SC When the gate of the control rectifier 8Creceives a discharge from condenser 17, the transistor SC becomesconductive and a current will pass via Q to the collector and thestarter motor which will be energized.

During that time, the oscillator comprising the transistor U becomescharged. At the end of the charging period, the controlled transistor 8Cbecomes conducting and by means of the capacitor 18 will block theconduction of the transistor SC,;. The starter motor will then stop. Thestarter motor in this embodiment is energized through the transistor Scand the transistors U and SO, function to stop its operation in adiscontinuous manner. This operation takes place until the motor runs oruntil the working period of U renders transistor S0 conductive and thusstops operation of Q Q and U If the motor has not started to run, adilference of potential will remain across the transistor 8C but willnot be sufficient to drain the battery.

If the motor starts to run, the oil pressure switch 19 will open thecircuits and the motor will keep running until the thermostat switchT.H. opens to break the circuit. It should be noticed that an oilpressure switch 19 may be used instead of a connection from thegenerator to open the circuit.

The embodiment shown in FIG. 4 may be considered a combination of theembodiments of FIGS. 1, 2 and 3. A power transistor Q;., is used inconjunction with relays K and L.

The switch TS is closed in a similar manner as in FIG. 1 which closesthe switch SW to the generator. When the thermostat has reached acertain temperature, its contact closes. It is obvious that instead ofthis contact, any other equivalent device may be used.

The following operations take place:

(a) The ignition coil is energized and the oscillators comprising U andU start to operate. The power transistor Q, is alternatively conductingthereby instituting starting and stopping of the starter motor.

('b) The delay switch generally indicated by U also starts to operateand will reach its Working period, the transistor Q, will then stop tofeed the starter motor.

If the motor starts to run, the cranking cut-out relay L is energizedthrough the generator AC. or DC. The contact L opens to eliminate theuse of the automatic system to leave only the ignition coil energizeduntil the thermostat switch TH opens its contact to stop the motor for aperiod of time that is, until the temperature has fallen below a certaindegree.

When the motor does not start before the end of a number of workingcycles of the oscillators U and U the time delay represented by U willprovoke the energization of the relay K so that its contacts K and Kwill disconnect the automatic system and the ignition coil.

The relay K will remain energized until the switch TS is opened but,again the weak current which is required, will not drain the battery.During the normal operation of the engine, the switch T.S. remains open.

The diodes 1 to 13 illustrated in FIGS. 1 to 4 are used as safetydevices to prevent a feedback of the current in an unwanted direction inthe circuit.

I claim:

1. An automatic motor starter comprising:

(a) a direct current power supply,

(b) a current establishing switch,

(c) a low frequency bi-stable trigger circuit comprising two time-delayswitches, each time-delay switch containing a low frequency oscillator,each oscillator oscillating alternatively,

(d) a third time-delay switch containing a third low frequencyoscillator, the frequency of the said third oscillator actuated to stOpthe operation of said trigger circuit after a determined number ofcycles of the said trigger circuit,

(e) a starter motor connected to each of the delay switches of saidtrigger circuit and adapted to ibe enerized when one of said delayswitches is conducting and deenergized when the other of said delayswitches is conducting,

(f) motor responsive switch means to be actuated when the motor isrunning to deenergize the three delay switches.

2. An automatic starter as recited in claim 1, wherein the establishingswitch is a thermostat switch for actuating the automatic starter whenthe temperature falls below a determined degree.

3. An automatic device as recited in claim 1, wherein each oscillatorcomprises a silicone unijunction transistor.

4. An automatic starter as recited in claim 1, wherein each delay switchcomprises a silicone unijunction transistor connected to a siliconecontrolled rectifier to actuate a relay switch.

5. An automatic starter as recited in claim 1, wherein the motorresponsive switch means is a cranking cutout relay.

6. An automatic starter as recited in claim 1, wherein the third delayswitch deenergizes an ignition coil.

7. An automatic starter for a motor comprising:

(a) a direct current power supply,

(b) a current establishing switch for feeding the direct current to anignition coil and to three time-delay switches,

(c) the first two delay switches operating alternatively as a lowfrequency bi-stable trigger circuit,

(d) one of said first two delay switches connected to a starter motorand adapted to operate the same when energized,

(e) the third delay switch operates at the end of a determined number ofcycles of said trigger circuit to deenergize the ignition coil and thefirst two delay switches.

8. An automatic starter as recited in claim 7, including a motorresponsive switch means to be actuated when the motor is running todeenergize the three delay switches.

9. An automatic starter as recited in claim 7, wherein said currentestablishing switch is a thermostat switch to actuate the automaticstarter when the temperature falls below a determined degree.

10. An automatic starter as recited in claim 7, wherein each oscillatorcomprises a silicone unijunction transistor.

11. An automatic starter as recited in claim 7, wherein each delayswitch comprises a silicone unijunction transistor connected to asilicone controlled rectifier to actuate a relay switch.

12. An automatic starter for an internal combustion engine comprising:

(a) a direct current power supply,

(b) a current establishing switch and a first relay connected in series,said first relay adapted to energize an ignition coil when the currentpasses through said first relay,

(c) a temperature controlled switch and three time delay switchesconnected in parallel with said temperature controlled switch and thefirst relay,

(d) the first two delay switches operating alternatively as a lowfrequency bi-stable trigger circuit,

(e) one of said delay switches connected to a starter motor and adaptedto operate the same when energized,

(f) motor responsive switch means actuated when the motor is running todeenergize the first relay and the three time delay switches.

13. An automatic starter as recited in claim 12, wherein theestablishing switch is a thermostat switch to actuate the automaticstarter when the temperature falls below a determined degree.

14. An automatic starter as recited in claim 12, wherein each oscillatorcomprises a silicone unijunction transistor.

15. An automatic starter as recited in claim 12, wherein each delayswitch comprises a silicone unijunctiontransistor connected to asilicone controlled rectifier to actuate a relay switch.

16. An automatic starter as recited in claim 15, wherein a relayactuated switch is alternatively actuated through a silicone controlledrectifier, to operate the starter motor.

17. An automatic starter as recited in claim 15, wherein the two relayactuated switches are alternatively actuated through a siliconecontrolled rectifier, to operate the starter motor.

18. An automatic starter for an internal combustion engine comprising:

(a) a direct current power supply,

(b) a current establishing switch and a first power transistor connectedin series,

(c) an ignition coil connected to said first power transistor,

(d) a bi-stable trigger circuit comprising two time delay switchesconnected to the collector of the said first transistor,

(e) the said trigger circuit comprising essentially a unijunctiontransistor and two silicone controlled rectifiers one of which applies acurrent through a second power transistor to actuate a starter motor,

(f) a third time delay switch connected to the base of the first powertransistor and operated at the end of a determined number of cycles ofsaid trigger circuit, to deenergize said trigger circuit,

(g) a motor responsive switch means to be actuated when the motor isrunning to deenergize the three delay switches.

19. An automatic starter as recited in claim 18, wherein the motorresponsive switch means is an oil pressure switch.

20. An automatic starter as recited in claim 18, wherein the motorresponsive switch means is a cranking cut-out relay.

21. An automatic starter as recited in claim 18, wherein.

the current establishing switch is a thermostatic switch.

22. An automatic starter for an internal combustion engine comprising:

(a) a direct current power supply,

(b) a current establishing switch,

(c) an ignition coil to be energized by the said current,

((1) a low frequency bi-stable trigger circuit connected to the directcurrent,

(e) the said trigger circuit comprising two time delay switches,

(f) a power transistor for conducting the current from one of said twodelay switches to a starter motor,

(g) a third time delay switch connected to the direct current powersupply and operated at the end of a determined number of cycles of thesaid trigger circuit to deenergize the said cricuit,

(h) motors means responsive switch to be actuated when the motor isrunning to deenergize the ignition coil and the third delay switch.

23. An automatic starter as recited in claim 22, wherein theestablishing switch is a thermostat switch to actuate the automaticstarter when the temperature falls below a determined degree.

24. An automatic starter as recited in claim 22, wherein each of thethree delay switches comprises a low frequency oscillator having asilicone unijunction transistor, a silicone controlled rectifierconnected to the said unijunction transistor.

25. An automatic starter as recited in claim 24, including a relayswitch connected in series with the silicone controlled rectifier of thethird delay switch, the said relay switch deenergizing the ignition coiland the flip-flop circuit.

No references cited.

ORIS L. RADER, Primary Examiner. G. SIMMONS, Assistant Examiner.

US. Cl. X.R.

